Mine conglomerate Anglo American is using an RFID system to track miners and prevent vehicle collisions at El Soldado, its underground copper mine in Chile. The system employs active 433 MHz RFID tags and RFID interrogators.
Of Anglo American's four Chilean mining sites, the smallest is El Soldado, about 80 miles north of Santiago. Safety concerns focus on knowing who is in the mine at any given time, in the event the mine needs to be cleared out for an explosion, or if there is an accident in the tunnels. Many miners in the two underground tunnels are private contractors, while others are Anglo American employees. To track the various individuals, El Soldado had been using proximity RFID cards.
Source: RFID Journal, http://www.rfidjournal.com